Objective: Although gastrointestinal symptoms are common immediate reactions to food allergies (FA), the relationship between acute pancreatitis (AP) and FA remains unclear.Patient: A 3-year-old boy developed vomiting, dyspnea, and urticaria 30 min after eating a cashew nut (CN) and was diagnosed with anaphylaxis.Results: The patient was diagnosed with AP based on markedly elevated serum pancreatic amylase activity (1,847 IU/L) and mild pancreatic enlargement on abdominal ultrasonography, despite the absence of abdominal pain. All symptoms resolved immediately after intramuscular adrenaline injection, and serum pancreatic amylase activity normalized after 3 days. CN allergy was diagnosed based on blood tests showing elevated serum levels of CN- and Ana o 3-specific immunoglobulin E.Conclusions: This is the first reported case of AP associated with anaphylaxis due to a CN allergy. AP should be considered in patients with FA who present with gastrointestinal symptoms, even if vomiting is the only symptom and abdominal pain is absent. AP associated with anaphylaxis may resolve rapidly with appropriate treatment.